The present invention relates to a process for precision folding metal sheet in a completely automatic manner. The present invention further relates to a folding installation for performing this process.
It is known that the precision folding of sheet metal is normally effected by means of particularly equipped folding presses served by operators who manually manipulate the sheet metal to be folded. The precision positioning of the sheet metal to be folded is obtained by bringing this up against movable reference abutments which are controlled by a numerical control which positions them from time to time in an appropriate manner. Such numerically controlled movable references, known with the technical name "back gauges" become substantially redundant if manipulation of the sheet metal in an automatic manner by means of robots is effected; in fact, the robots are themselves the numerically controlled devices; these, however, have the necessary positioning precision only for relatively small movements and therefore it is not currently possible, if it is desired to obtain high working precision, to do away with the auxiliary positioning devices and rely for correct positioning of the sheet metal solely on the manipulator robots. On the other hand the use of "back gauges" modified in a manner such as to adapt them to operate together with a robotised manipulator would involve the provision of automatic folding installations of high cost by way of the duplication of the numerically controlled devices (one for the movable references and one for the robots).